Brake Assist System
Here is what Mercedes-Benz says about it:
The Brake Assist System (BAS), an electronic system by Mercedes-Benz, interprets the braking behavior of the driver and initiates the full braking effect when it identifies an emergency situation. This reduces the braking distance substantially.
Here is the engineering foundation for BAS:
Conventional braking systems usually use engine vacuum to
increase braking capability. Instead of relying solely on vacuum power to
provide effective brakes, an electric pump pressurizes brake fluid to provide
power assist for BAS and the necessary brake force for 4ETS.
Most drivers, under normal braking conditions as well as under emergency conditions, start out with little brake pressure and whenever necessary they will increase their pedal effort. In an emergency this behavior leads many times to a crash since the car could not be stopped in time. Those situations require maximum pedal pressure from the beginning - if necessary the effort can be reduced later in the process.
With other words most drivers do not use the ability of the brakes to their advantage - BAS automatically corrects that. The system recognizes emergency situations within milli seconds and releases pressurized brake fluid into the system as soon as the driver touches the brake pedal. As soon as the driver releases the brake pedal, BAS kicks back into a standby mode.
BAS creates a much higher stopping force for emergencies than
most drivers are ever able to generate. By doing so BAS helps to prevent
Just another good reason to drive a car made by Mercedes-Benz